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The Porsche Marin Team

Our Porsche Team

Let us introduce you to our staff, show you some of our special vehicle offers and take you through our complete line of new, Certified pre-owned and used inventory. We can help you find exactly what you are looking for.

We know your time is valuable. We are sure you will find our site a fast and convenient way to research and find a vehicle that's right for you. If we can be of any assistance while visiting us online, send us an email and we will promptly reply. We look forward to serving you!

Most of our staff has been with Porsche Marin for more than 10 years.


Peter  Sonnen

Peter Sonnen | Dealer Principal

Mr. Sonnen has over 50 years in the car business and owns multiple dealerships worldwide. A Bay Area resident for over 30 years, Peter is from Germany and takes pride in the fact that over half of our technicians at Sonnen Porsche are also German. Porsche is Peters passion, and he not only owns the dealership, but used to also own his own racing fleet! He is an active member with the Bach Society, and a supporter for the Porsche Club of America.

Bill  Lamphere

Bill Lamphere | General Manager

Bill started selling cars while attending the University of Colorado in 1986. After graduation he decided that the car business was a perfect match for him. In his 30+ years he has worked with Toyota, BMW,Lexus and Porsche.His favorite Porsche is the 911 GT3. In his spare time,Bill enjoys skiing, amateur road racing, golf, and spending time with family and friends.

Phone: 415.380.8000 • Email:

Tim Mattos

Tim Mattos | General Sales Manager

Tim has been in the car business since 1983. He was born and raised in Marin county and has lived here for over 58 years. Tim likes the outdoors, playing golf, and sports of all kinds. Tim has three young adult kids, parents, brothers, and sisters that all live in the area. 

Phone: 415.380.8000 • Email:

Emil  Rustamov

Emil Rustamov | Finance Director

Emil has been in the car business since 1998. His favorite model is the Carrera 911. He enjoys playing guitar and listening to jazz as well as flamenco music in his spare time.

Phone: 415.380.8000 • Email:

Kia Afra

Kia Afra | CPO Manager

Kia is a local Marin resident who's been working in the car business for over 20 years. His favorite Porsche is the Macan S because of its all-around utility.

Phone: 415.380.8000 • Email:

Kevin Johnson

Kevin Johnson | Service Manager

Kevin recently joined the Porsche Marin team with over 30 years experience in the service department. He has worked with several luxury brands and brings a can do attitude and client focussed processes to our team. His favorite Porsche is the Macan Turbo.

Phone: 415.380.8000 • Email:

Greg  Arteche

Greg Arteche | Parts Manager

Greg has 34 years in the car business, 28 of those being with Porsche. Greg loves the 993 turbo because of its design and the fact that it's the last air-cooled 911.

Phone: 415.380.8000 • Email:

Gary  Wright

Gary Wright | Porsche Certified Brand Ambassador

Gary Wright has been with our Sonnen Service team from the start. He has a loyal customer base and it shows in his customer reviews!

Fax:   415-380-0540

Phone: 415.380.8000 • Email:

Tristan  Bayless

Tristan Bayless | Porsche Certified Brand Ambassador

A Jim Russell Certified Racecar Mechanic with his focus in delivering comprehendible repair explanations, Tristan got his start in the automotive world with RUF Automobile GmbH selling ex-works performance parts all over the world.  His favorite Porsche is a championship-winning 1968 912 he autocrosses locally with a close family friend.

Contact directly at:   415-381-7823

Fax:   415-380-0543

Phone: 415.380.8000 • Email:

Sanders Delars

Sanders Delars | Shop Foreman

Sanders is a Porsche Gold level technician and aspiring shop foreman.

Phone: 415.380.8000 • Email:

Paul  Dulberg

Paul Dulberg | Porsche Brand Ambassador

Paul has been selling Porsches for over 12 years now. He is super savvy with all things jazz, tech and Porsche related.

Fax: 415-380-0540

Phone: 415.380.8000 • Email:

Stephen  Poulden

Stephen Poulden | Porsche Brand Ambassador

Stephen has been in the car business for over 25 years, 12 of them with Porsche. He is a Porsche Brand Ambassador.

Phone: 415.380.8000 • Email:

Michael  Gray

Michael Gray | Porsche Brand Ambassador

Michael Gray has 25 years in the car business, 10 of those with Porsche. He is a Porsche Brand Ambassador.

Fax: 415-380-0540

Phone: 415.380.8000 • Email:

Brett  Payne

Brett Payne | Porsche Brand Ambassador

Brett is another one of our world travelers, is an expert on Porsches, and has been in the business for 15 years.

Fax: 415-380-0540

Phone: 415.380.8000 • Email:

Andrew  Proaps

Andrew Proaps | Porsche Brand Ambassador

Andrew has over 15 years of experience in the automotive world and comes from a family deeply rooted in Marin. His favorite Porsche is the 911 Turbo cabriolet in Anthracite.

Mobile: 415.250.6911

Phone: 415.381.7817 • Email:

Ron de Vogel

Ron de Vogel | Sales and leasing

Ron is a Tiburon resident and has been in the car business for more than 30 years. Ron is an avid car racer and motorsports fan. His favorite car is the Cayman GT4.


Phone: 415.336.5622 • Email:

Monica  Guzman

Monica Guzman | Administrative Assistant

Monica has been in the car business since 1996. She previously worked at Sonnen BMW based in San Rafael, a company that Peter Sonnen himself helped establish. Monica is a mother of three and loves to spend time with her family. Her favorite Porsche is the Panamera because it accomodates her family comfortably.

Contact directly at: 415-380-8000

Fax: 415-380-0540

Phone: 415.380.8000 • Email:

Julian Rubbo | Salesman

My favorite model has to be the Porsche 911 Targa. I enjoy restoring old cars. This is my ninth year in the automotive industry.